Open the VoiceOver Help Menu with the keyboard shortcut Control, Option, H.

To navigate through the items on the Help Menu use the Up and Down Arrow keys on your keyboard. To open a submenu, press the Right Arrow key. To go back to the previous menu, press the Left Arrow key on your keyboard. As you select each menu item, VoiceOver will read back the selected item and its associated keyboard shortcut if one is available.

To close the VoiceOver Help Menu, press the Escape key on your keyboard.